This Core coordinates patient enrollment, organizes clinical data, and standardizes collection of clinical specimens and bioassays. In so doing, the Core will leverage the large cohorts of patients with Pulmonary Arterial Hypertension (PAH), at risk for Ventilator Induced Injury of the Newborn Lung (VIINL) or chronic lung disease (CLD) and candidates for Lung Transplantation (LT) followed at the Stanford. They will carry out an established platform of state-of-the-art bioassays for cells and fluids that will be related to physiological endpoints that reflect disease severity.